Samsung SMH7185, Troubleshooting

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SMH7185 1/20/2012 3
CN05 Gas Sensor
3-
4 5vdc
CN202 Pwr & Relay
1-(CN201-1) Main
3-(CN201-1) Turntable, stirrer
5-(CN201-1) Vent Low
7-(CN201-1) Vent High
9-(CN201-1) Vent Boost
Main PCB
CN201 Relay, Lamp, SMPS
1 Line 1
3-1 RY202 In Rush Relay Neutral Contact
5-1 RY206 Bright Lamp Relay Neutral Contact
5-1 RY205 Night Lamp Relay Neutral Contact
7-NC
RY203
Power
High Relay
RY209
Fan
high
RY208
TT
RY201
Main
Relay
RY05
Night
Relay
RY206
Bright
Relay
RY202 In
Rush Relay
Door Interlock
CN401 Door Connector
1 Door sw
3 Door sw 12vdc
5 Gnd
4 Hood TCO 5vdc
The fuse is located on the noise filter.
1. Disconnect power and remove grille and Assembly Control Box.
2. Replace the fuse.
3. When 20A fuse blows out by the operation of interlock monitor
switch failure, replace the primary interlock switch, secondary inter-
lock switch, door sensing switch, interlock monitor switch and power
relay.
4. When the above four switches operate properly, check if any
other part such as the control circuit board, blower motor or high
voltage transformer is defective.
CN01
1) KEY OUT-1
2) KEY OUT-2
3) KEY OUT-3
4) KEY OUT-4
5) KEY OUT-5
6) KEY OUT-6
7) KEY OUT-7
8) KEY OUT-8
9) KEY OUT-9
10) KEY IN-1
11) KEY IN-2
12) KEY IN-3
13) KEY IN-4
14) KEY IN-5
15) KEY IN-6
16) KEY IN-7
RY204
Power Low
Relay
Microwave cover assembly
The front of the top cover has flanges that must fit inside the front frame and vent, and the bottom goes above the bot-
tom cover. Start with the left side and hold in place with one screw once engaged. Leave the display loose so you can
see that the right side is engaged properly. Then mount display and the vent, ensuring the vent engages the flange.
RY209
Fan
low
RY209
Fan-
boost